Online services provide useful information about an entity of interest. For example, some social networking services provide ratings for quality and price-friendliness of restaurants and coffee shops based on user reviews and/or exclusive reviews by agents. While such information can be handy and useful, it can be unreliable because the information source, from which the ratings are generated, can be unreliable. For example, reviews from certain users can be deliberately misrepresentative because those users may have other ulterior motives. Even if the information source is reliable, the information can be biased because the information is derived from biased sources or a small number of sources. When there are only few reviewers, the information has low statistical significance.